Flying colours
Early autumn is a perfect time to brighten your garden with vivid dahlias and sedums
I hope you are all enjoying the September sunshine and getting to spend some extra time outside. While gardens can look a bit tired at the end of August, by September there are many species which are just beginning to shine.
In addition, some plants such as roses, achilleas and antirrhinums are providing their second, albeit smaller, flush of flowers.
Add to this the stalwarts such as Geranium Rozanne, which continuously flower from May to November, and you could be enjoying a very colourful garden right now.
Dahlias are the backbone of the September garden and they make great long-lasting cut flowers. They fell out of fashion but for those of us who like to extend the gardening season as late as possible, they’re definitely in. If you haven’t tried growing them before, I would recommend ‘Karma Choc’, which bears delicious rich dark black-red flowers atop bronze foliage and is chocolate scented. ‘Twynings After Eight’ is also a beauty – single white flowers on black foliage. You can grow dahlias from tubers or rooted cuttings in spring. As they are from Mexico, they like to bask in the sunshine, so choose a southfacing position and prepare the soil with plenty of manure as they are greedy feeders. And remember they are tender – they will need to be lifted and stored indoors as soon as frost blackens their foliage.
Sedum, the ice plant, is a deservedly popular perennial that will do sterling work from now until November. It’s easy to grow and low maintenance. Its fleshy succulent stems are able to store water so it’s very drought tolerant.
It will grow better on average to poor soil because in very fertile soil it can get a bit too lush and droopy – so don’t feed it.
The best known variety is ‘Autumn Joy’ with its rosy pink flowers but there’s a new kid on the block called ‘Jose Aubergine’ which has purplish aubergine coloured stems and dusky pink flowers.
It’s a bit stouter than some of the other varieties and less likely to flop over.
Sedums are very attractive to butterflies and bees who are grateful for the late summer pollen and they look fantastic paired with grasses such as Hakonechloa or Stipa teniussima.
Plant some mauve Verbena bonariensis which will drift through and provide vertical height to create a delightful early autumn border. And what about alstromerias? They look quite exotic but many are perfectly hardy.
This tuber is from South America and is known as the Peruvian lily.
The range of colours is vast – white, yellow, apricot, orange, pink, red, purple and lavender – and considering their long flowering period, they are a bit underrated.
In order to keep the flowers coming, remove the entire stem when flowering is finished – don’t just deadhead.
These are best planted from pots as tubers often fail to grow and can be vulnerable to disease.
Lovely varieties include ‘Apollo’ which is white with a yellow throat, ‘Indian Summer’ with orange yellow flowers and attractive bronze foliage, and ‘Purple Rain’ which has large – you guessed it –purple flowers.
Finally, Rudbeckia will provide golden highlights in the garden even when the sun isn’t shining.
These wonderful daisy-like yellow flowers have a central dark cone so are known as Black-eyed Susans.
They’re easy to grow and will keep clumping outwards so you could divide every few years.
September is a good time for planting perennials as the ground is still warm but the plants are less likely to dry out.
So whether you’re filling gaps in the border or having a rethink about your plants, consider introducing some late colour that will provide a cheerful picture over the coming months.